URINE ANALYSIS

Forensic Science Project

Activity Objectives

During this activity you should be able to:

• Conduct various tests on a known urine sample to identify characteristics of urine
• Identify the characteristics of an unknown urine sample

Procedure

Design a table for your results. The table should have space to record your data and drawings for eight tests on one known sample and two unknown samples.

Part 1 Initial Examination of Urine

• Examine the labeled urine sample for odour. Describe the odour you smell .
• Comment on the colour of your sample. Use terminology such as yellow, amber, dark pale etc.
• Describe the clarity of your sample. Use terminology such as clear, cloudy etc.

Part 2 - Determining Specific Gravity

• Remove the hydrometer from its cylinder and empty the water from the cylinder into the sink. Fill the hydrometer cylinder three quarters full with the urine sample
• With a spinning motion, float the hydrometer in the urine. Be sure that the hydrometer stays suspended in the urine and does not adhere to the sides of the cylinder
• When the hydrometer has stopped spinning and is not touching the sides of the cylinder, read the specific gravity of the sample at the bottom of the meniscus formed at the hydrometer column. Record the specific gravity
• Pour the urine sample in the hydrometer cylinder into a test tube for Part 3 and 4 of the activity. Pour any remaining urine back into your sample container.
• Rinse and fill the hydrometer cylinder with water and place the hydrometer in the water,

Part 3 - Testing for pH

• Tear off about 3 cm of pHydrion pH test paper
• Remove your test tube and dip the pH paper in the urine
• Remove and compare with coloured pH scale provided
• Record pH in your table

Part 4 - Sediment Analysis

In this part of the activity you will be looking for blood cells, crystals and phosphate granules in the urine sample. The presence of blood cells in the urine may be indicative of an abnormal condition, while the crystals may indicate the presence of drugs.

• Fill one small test tube with the urine sample
• Set the tube in the centrifuge opposite someone else's sample and spin for five minutes. (Please check with the teacher that your setup is correct before you turn on the centrifuge)
• After centrifuging, pour off the liquid or supernatant and place into a clean test tube. Place the test tube to the side to be used in part 5.
• Shake the test tube to re-suspend the sediment in the small amount of urine left in the test tube. Pour this onto a slide and prepare a wet mount to observe under the microscope.
• Describe the sediment you observe under the microscope. (Remember to include any blood cells, phosphate granules or crystals you observe.)

Part 5 - Testing for Albumin (protein)

• Observe and record the clarity of the supernatant
• Separate the supernatant into two parts. Place one part to the side for use in Part 6
• Place the second part of the supernatant in a test tube and place in a hot water bath.
• Compare the cloudiness of the heated supernatant with the unheated portion of the supernatant. If cloudiness increases in the heated sample, then protein is present.

Part 6 - Testing for Glucose

• Add 10 drops of Benedict's solution to the unheated portion of the supernatant from part 5
• Fill a second test tube one quarter full of water and add 10 drops of Benedict's Solution (this is the control)
• Boil both test tubes for 4-5 minutes and then allow test tubes to cool
• An orange precipitate will form when glucose is present.

Part 7 - Analysis of Unknown Urine Sample

You will be required to complete an analysis on one unknown urine sample using the procedures you have learned in parts 1 to 6.

• Obtain 50 ml of one of the unknown urine samples
• Perform the urine analysis procedure on your unknown sample and compare the results to the known sample.

Reflections on the Activity

1. Using your library, local medical professionals and/or the Internet, determine what are the normal ranges of the tests you have completed for human urine. Pick one specific test and research the possible diseases or medical illnesses that can occur if a person exceeds the normal range.

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